1 Scope This British Standard gives recommendations and guidance on the procedural controls to be applied to all aspects of temporary works in the construction industry. It also includes guidance on on permissible stress design of all falsework. The guidance also applies to the design of class A falsework 1 Section 1 gives recommendations in relation to training and education. Section 2 gives recommendations for procedures to ensure that temporary works are conceived, all construction projects. These procedures include clauses relating to all roles involved in temporary works: clients, permanent works designers, temporary works designers, contractors (including construction management organizations), suppliers and manufacturers. Construction sites and methods adopted for controlling the temporary works vary. This British Standard recognizes that the extent of control measures required are greater on the larger or more complex projects, as can be encountered on major infrastructure projects, power stations, airports procedures might be required on major infrastructure projects. Section 3 covers the design of temporary works and in particular the design of falsework and relevant formwork. In addition Section 3 covers: materials including material factors; loads and load factors; design of falsework, including both proprietary equipment and traditional scaffolding solutions; wind loading (reference to temporary and permanent stability) and reference to other British Standards for the design of structural steelwork, reinforced concrete and excavation support. Although Section 3 was written for permissible stress design, the design concepts and the service loads stated are applicable to limit state design. The loads, including wind loads, are the unfactored service loads and conform to both BS EN 1991-1-4 and BS EN 12812. The structural design element in this British Standard is additional information necessary for the structural design of falsework. It can be used in conjunction with existing structural standards. 2 Normative references The following documents are referred to in the text in such a way that some or all of their content constitutes provisions of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. 2 BS 449-2:1969 (withdrawn), Metric units BS 648 (withdrawn), Schedule of weights of building materials 1 BS EN 12812 states that design class A is only to be adopted where: a) slabs have a cross-sectional area not exceeding 0.3 m 2 per metre width of slab; b) beams have a cross-sectional area not exceeding 0.5 m 2 ; c) the clear span of beams and slabs does not exceed 6.0 m; d) the height to the underside of the permanent structure does not exceed 3.5 m. 2 As Section 3 has not been updated as part of this revision, it refers to some standards which have now been withdrawn. These have been marked as such. BS 5975:2019 BRITISH STANDARD
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1 ScopeThis British Standard gives recommendations and guidance on the procedural controls to be
applied to all aspects of temporary works in the construction industry. It also includes guidance on
BS 1881-119, Testing concrete — Part 119: Method for determination of compressive strength using ���� ����������������U��� �����=����^�~� ;�����������������_
BS 1881-120 (withdrawn), Testing concrete — Part 120: Method for determination of the compressive strength of concrete cones
BS 5930:1999, Code of practice for site investigations
BS 6399-1 (withdrawn), Loading for buildings — Part 1: Code of practice for dead and imposed loads
BS 8002, Code of practice for earth retaining structures
BS 8110-1 (withdrawn), Structural use of concrete — Part 1: Code of practice for design and construction
BS 8110-2 (withdrawn), Structural use of concrete — Part 2: Code of practice for special circumstances
BS 8110-3 (withdrawn), Structural use of concrete — Part 3: Design charts for singly reinforced beams, doubly reinforced beams and rectangular columns
BS EN 39:2001, Loose steel tubes for tube and coupler scaffolds — Technical delivery conditions
BS EN 74-1, Couplers, spigot pins and baseplates for use in falsework and scaffolds — Part 1: Couplers for steel tube — Requirements and test procedures
BS EN 1011-1, Welding — Recommendations for welding of metallic materials — Part 1: General guidance for arc welding
BS EN 1011-2, Welding — Recommendations for welding of metallic materials — Part 2: Arc welding of ferritic steels
BS EN 1065:1999, [������������������ ���������������]����������� � ��� ���Z���� �������������������#�calculation and test
BS EN 1313-1:1997, Round and sawn timber — Permitted deviations and preferred sizes — Part 1: Softwood sawn timber
document that lists activities that need inspection and/or testing
NOTE 1 This list could be available as either a generic list, as an aide-memoire on a particular subject, or as a ���� � ��� �����~���� ���������� ; � ��� ���������������K
NOTE 2 This can be enhanced with a signature to verify that the work has been completed satisfactorily as part of the management process.
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3.12 client
organization or person for which/whom a construction project is carried out
3.13 competent person/organization
person/organization with the necessary skills, knowledge and experience (and organizational
any person (including a non-domestic client) who, in the course or furtherance of a business, carries
out, manages or controls construction work
NOTE 1 Anyone who directly employs or engages construction workers or manages construction is a contractor. Contractors include principal contractors, sub-contractors, any individual, sole trader, self-employed worker, or business that carries out, manages or controls construction work as part of their business. This also includes companies that use their own workforce to do construction work on their own premises. The duties on contractors apply whether the workers under their control are employees, self-employed or agency workers.
NOTE 2 Where contractors are involved in design work, including for temporary works, they also have duties as designers under the CDM Regulations 2015 [1].
document prepared by the designer outlining the means by which the design is to be developed, the
assumptions, method of analysis and other controls
NOTE The design statement can include the potential of the temporary works to affect/impact operational infrastructure.
3.19 designated individual (DI)
senior person within an organization with responsibility for establishing, implementing and
maintaining a procedure for the control of temporary works for that organization
3.20 domestic client
client for whom a project is being carried out which is not in the course or furtherance of a business
of that client
NOTE Local authorities, housing associations, charities, landlords and other businesses might own domestic properties, but they are not considered to be a domestic client for the purposes of the CDM Regulations 2015 [1]. If the work is in connection with a business attached to domestic premises, such as a shop, the client is not a domestic client.
3.21 effective length
theoretical length of a compression member as determined by the restraint at its ends
3.22 factor of safety
ratio of failure load to the maximum working load
3.23 falsework
temporary structure used to support a permanent structure while it is not self-supporting
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beam of adjustable length, usually a metal lattice or sheet metal box beam, used to support decking
competent person with responsibility for the co-ordination of all activities related to the
temporary works
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competent person who is responsible to and assists the temporary works co-ordinator
3.53 third party
party, independent of the project, whose procedures are to be followed, and approvals obtained, for
temporary works proposals affecting their assets, users or their land ownership
NOTE An example of a third party would be a highway authority, affected by a new rail structure over their asset, required as part of the client’s project.
metal decking) after the completion of the permanent works, but in the latter case would not
necessarily contribute to the strength of the permanent works.
5.1.1.3 When a project has, or might be anticipated to have, the requirement for any temporary works,
all organizations involved in the management of the temporary works, whether implemented by
themselves or others, should have and implement a procedure which outlines how they are to
discharge their duties in relation to the temporary works.
NOTE The purpose of the procedures is to manage and control the organization’s involvement both within their own organization and when they are employing others or working with other organizations to carry out temporary works roles.
5.1.1.4 This overview explains the core principles and organizational interfaces which are recommended,
before expanding on the procedural control details in Section 2.
5.1.1.5 All types of organizations, from the use of temporary works by small contractors to the very large
organizations and/or utilities should use the procedures outlined in detail below. This includes civil
engineering companies and building companies. The approach adopted in Section 2 is “organization
focused” so the procedures for each organization are separated – it is accepted that this includes
some duplication of text.
NOTE The term "organization" includes clients, designers, permanent works designers, temporary works designers, principal designers, contractors, principal contractors, sub-contractors, specialist contractors, third-party contractors and supplier/manufacturers.
5.1.1.12 The third principle (see 5.1.1.10) that one person is to be appointed with overall responsibility for
�� ���!���������U�;��>������ ���;��� ��������� �!��� ��!��J������������2]. A temporary
works co-ordinator (TWC) should be appointed with overall responsibility for managing the
temporary works on a site. This person should be appointed by the principal contractor and should
be referred to as the “PC’s TWC”.
NOTE The TWC can, if necessary, delegate certain day to day activities, such as site inspection, to a temporary works supervisor (TWS).
5.1.1.13 A TWC may be appointed by another contractor to manage their temporary works but this individual
should be responsible both to their DI and the PC’s TWC.
NOTE The term “contractor” is taken to mean sub-contractor employed by the PC or a contractor employed directly by the client or a third party (see 3.15).
5.1.1.14 Many of the duties of the DI, the PC’s TWC, TWC and TWS detailed in this British Standard are
activities already being carried out "as routine" by competent persons in the construction team. The
activities of these individuals should be formalized in company procedures in accordance with the
various clauses below to ensure the temporary works are implemented in a controlled manner. Only
5.1.3.1 There are many combinations of organizations that can be involved in temporary works. They can
include clients, management contractors, contractors, sub-contractors, utility authorities, service
suppliers (M&E), equipment suppliers, consultants and specialist contractors. Each have different
contractual arrangements from project to project but the over-arching principle is that the PC’s TWC
has overall responsibility on site.
5.1.3.2 The framework of contractual relationships should be taken into account when planning the
management of temporary works; an overview of likely contractual relationships between clients,
contractors and designers, including both permanent work designers (PWDs) and temporary works
designers (TWDs) is shown in Figure 1. Figure 1 also demonstrates the typical links showing how the
designers should co-operate, even when not in a contractual relationship (shown as dashed).
Figure 1 — Typical contractual interfaces between parties on a project
NOTE 1 Attention is drawn to the CDM Regulations 2015 [1], which require the principal designer to take responsibility for all designers on that project and to co-operate, co-ordinate and transfer relevant information – this is shown by a dashed line.
NOTE 2 There is rarely a contract between the principal contractor and a client’s contractor.
5.1.4 Responsibilities where a contractor co-ordinates the temporary works
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The various ways in which the control measures (see 5.1.2) are likely to be implemented on different
projects of varying complexity are shown as lines of responsibility in Figure 2. In all the cases the
sole contractor or principal contractor should manage and co-ordinate the temporary works on the
project themselves.
5.1.4.2 Small contracts
Small contracts, including domestic client projects, often have only one contractor. This is
shown in Figure 2a) and applies to the majority of small organizations, including builders and
Figure 3 — Lines of responsibility where either a principal contractor's (PC) appointed sub-contractor or a client's contractor co-ordinate their own temporary works
a) PC appoints a sub-contractor to co-ordinate their own temporary works
NOTE The PC’s designated individual (DI) has to approve the managing sub-contractor’s temporary works procedures before appointment of the TWC.
b) Client-appointed contractor to co-ordinate their own temporary works
NOTE The PC’s designated individual (DI) has to approve the client contractor’s temporary works procedures before appointment of the TWC.
Figure 4 — Schematic representation of relationships between principal contractor and contractor (client appointed or sub-contractor) including PC’s TWC and contractor’s TWC
The PC’s TWC should control the other temporary works on the site, and liaise with other contractors,
to control the various interfaces.
NOTE For example, a RC frame contractor would not necessarily be aware that a ground work sub-contractor was digging a trench across the site close to the RC frame construction.
5.1.5.3 Client-appointed contractor
Where a client appoints a contractor directly and where the work has a temporary works element,
satisfactory and the client’s contractor should appoint a TWC to control their temporary works [see
Figure 3b)].
The TWC should report to the PC’s TWC and provide a method of communication to liaise between
the site and the other contractors for temporary works.
As there is no contract between the parties involved in the temporary works (see Figure 1), the
client should take into account that any such appointed contractor should be made aware of the
implications and the continuing role of the PC’s TWC on the project. This should be made clear to any
contractor appointed by the client at an early stage in the procurement/management process.
5.2 Training
COMMENTARY ON 5.2
������������������������� � ���������������U��+�����������������#�+��U������;�����������������= �#����the project. Although it is desirable that temporary works is included in college and university courses, detailed practical knowledge of the subject is gained through practice. This knowledge is gained by observation, by CPD, or by experience, supplemented by regular training.
It is desirable that universities and colleges include temporary works within the syllabus for building, construction and civil engineering courses.
Although detailed technical knowledge on temporary works has historically been considered necessary for contracting staff, the experience and understanding of the effect of temporary works on design and construction leads to a broader based understanding and a more informed student. This promotes better design of permanent works and better informed engineers joining the construction industry.
A syllabus would be expected to include an introduction to the types of temporary works, both above and below ground; an understanding of likely management processes to be adopted to control the temporary works, with, where possible, indications of the cost implications of temporary works. Temporary works involves assessment of risk, and it is expected that risk management would already be included in the syllabus.
In addition to a general awareness of temporary works, the more commonly occurring temporary works of trenches, scaffolding, backpropping, crane pad foundations, hoardings etc. might justify more detailed coverage on most courses. It is desirable that the principles of stability of temporary works structures are included in this syllabus.
It is also desirable that non-technical courses at colleges and universities for subjects such as quantity ���;�# ��Z��� �� �����������������K� ��������+�������� ����������#�+��U�K��� ��� �� � �����#� ����;���the recognition of temporary works as an important element in construction, contributing to safer, more economical construction.
College and university lecturers are advised to use CPD to keep up-to-date with the latest temporary works subjects, to ensure they have relevant knowledge and technical experience in temporary works.
5.2.1 All those managing temporary works should have, as a minimum, an understanding of:
a) the procedures outlined in Section 2 of this British Standard;
training (e.g. railway work, demolition, airports, tunnelling, oil and gas): where required, this should
be established at an early stage of the project.
NOTE 1 Typical courses for general awareness and practical and technical knowledge are often only one day, increasing to two days for more technical design and awareness courses. Detailed temporary works design courses ��������� ����������������� ����������� ������ ����������� � ��� ������U��+���������� ����������#�+��U���������������three or four days duration and are often in-house.
NOTE 2 Temporary works is essentially very practical, with attention to details often being critical, so on-line training or self-taught with mentoring might also require practical assessment.
5.2.3 Those procuring training should assess the actual trainer for competency, not the training provider;
to ensure that the trainer has the relevant and up-to-date technical or practical experience in
temporary works.
NOTE 1 Whereas risk management and procedural aspects of temporary works training can be carried out by safety professionals and/or competent skills centre tutors, they are unlikely to have the necessary understanding in ����� ���������������� �����������������������#�+��U�������� ��#������ � ������� � �����~� �������� ���� � ��� ��5.2.1d) and 5.2.1e).
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